Perinatal mood disorders disproportionately affect low-income women with rates as high as 25-30%, twice that of the general population (14%). When untreated, these vulnerable women and their children suffer from its acute and long term effects. Effective treatments, such as antidepressants and psychotherapy, exist. However underserved women often are not able to access them, actively engage in them and/or adhere to them for a variety of reasons. Impoverished women encounter a host of barriers to accessing care, including practical (i.e. childcare, transportation), societal (embarrassment, family/friends disapprove, work responsibilities) and emotional (too tired to seek care, fear a new system) barriers. To overcome these barriers, we propose a model in which mothers have easy access to proven, effective depression treatments (interpersonal psychotherapy and/or sertraline) in a setting that they frequent (the pediatric clinic), from providers who are familiar to them and who can help to assess and address individual barriers to engaging in and adhering to treatment (the pediatric social worker and the psychiatric nurse practitioner). To develop this novel model we propose to adapt standard collaborative care depression treatment in two unique ways: 1) to the needs and preferences of low- income, urban mothers with perinatal depression;and 2) to the pediatric clinic setting - a setting in which mothers typically do not receive care. The primary outcomes sought from the new model are increased engagement in and adherence to depression treatment. The project involves two phases of model development. Phase I includes the development (through maternal and provider interviews), feasibility testing and refinement of the procedures. Phase II is a pilot randomized controlled trial comparing the new model to enhanced referral as usual. The findings from this study will provide the preliminary data required to conduct a multi-site practice-based efficacy study of the new model. If effective, this model will be widely disseminated and will have far reaching effects on women and children by improving the mental health of a vulnerable population - underserved, low-income, urban mothers. Disadvantaged women, who have high rates of perinatal depression, experience many barriers to receiving care. By providing tailored maternal depression treatment in the pediatric clinic, mothers will have ready access to and receive the treatment they need.